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Air Force Reserve Force Structure Policy Evaluation Model, Scott A. Percival
Air Force Reserve Force Structure Policy Evaluation Model, Scott A. Percival
Theses and Dissertations
The United States Air Force Reserve is a constantly changing force. In response to these changes, the Active Guard Reserve (AGR), a small organization within the Reserve, is seeking to create a career track for Unit and Headquarters' Officers. It is necessary for the AGR policy division to be able to evaluate the availability of career paths to accomplish this goal. The Air Force Reserve Force Structure Evaluation Model provides the AGR management with a tool to aid them in evaluating policy impact. This model allows the AGR management to identify the impact policy changes may have on the resulting …
An Investigation Of The Effects Of Correlation In Sensor Fusion, Susan A. Storm
An Investigation Of The Effects Of Correlation In Sensor Fusion, Susan A. Storm
Theses and Dissertations
This thesis takes the first step towards the creation of a synthetic classifier fusion-testing environment. The effects of data correlation on three classifier fusion techniques were examined. The three fusion methods tested were the ISOC fusion method (Haspert, 2000), the ROC "Within" Fusion method (Oxley and Bauer, 2002) and the simple use of a Probabilistic Neural Network (PNN) as a fusion tool. Test situations were developed to allow the examination of various levels of correlation both between and within feature streams. The effects of training a fusion ensemble on a common dataset versus an independent data set were also contrasted. …
Shortest Path Problems In A Stochastic And Dynamic Environment, Jae Il Cho
Shortest Path Problems In A Stochastic And Dynamic Environment, Jae Il Cho
Theses and Dissertations
In this research, we consider stochastic and dynamic transportation network problems. Particularly, we develop a variety of algorithms to solve the expected shortest path problem in addition to techniques for computing the total travel time distribution along a path in the network. First, we develop an algorithm for solving an independent expected shortest path problem. Next, we incorporate the inherent dependencies along successive links in two distinct ways to find the expected shortest path. Since the dependent expected shortest path problem cannot be solved with traditional deterministic approaches, we develop a heuristic based on the K-shortest path algorithm for this …
Building Blocks For Time-Resolved Laser Emission In Mid-Infrared Quantum Well Lasers, Gabriel D. Mounce
Building Blocks For Time-Resolved Laser Emission In Mid-Infrared Quantum Well Lasers, Gabriel D. Mounce
Theses and Dissertations
The objective of this research is to improve the performance of mid-infrared semiconductor quantum-well lasers. Lasers operating in the mid-infrared are useful for many Air Force applications which include infrared (IR) countermeasures in particular. Countermeasure applications require lasers that are compact, and able to emit at high powers while operating at room temperature. Limits to power increases are seen in the transverse modal development of laser oscillation. These modes typically form in the waveguiding active region contributing to the laser output. However, competing modes outside of this region also develop when the confining structural layers have the right characteristics. These …
Fast Compression Of Imagery With High Frequency Content, D. Scott Anderson
Fast Compression Of Imagery With High Frequency Content, D. Scott Anderson
Theses and Dissertations
Image compression is an active area due to the many applications involving electronic media. Much research has been focused on image quality versus bit rate and/or algorithm speed. Here, we seek an effective image coder with a weighted constraint on speed. However, the compression must not taint the quality of impulsive features on the image. Moreover, the camera is operated in a mode that creates a dominant fixed pattern noise across the image array, degrading visual quality and disrupting compression performance. We propose a method that efficiently compresses such an image. We begin by characterizing and removing the fixed pattern …
The Generalizability Of Private Sector Research On Software Project Management In Two Usaf Organizations: An Exploratory Study, Michael R. Garman
The Generalizability Of Private Sector Research On Software Project Management In Two Usaf Organizations: An Exploratory Study, Michael R. Garman
Theses and Dissertations
Project managers typically set three success criteria for their projects: meet specifications, be on time, and be on budget. However, software projects frequently fail to meet these criteria. Software engineers, acquisition officers, and project managers have all studied this issue and made recommendations for achieving success. But most of this research in peer reviewed journals has focused on the private sector. Researchers have also identified software acquisitions as one of the major differences between the private sector and public sector MIS. This indicates that the elements for a successful software project in the public sector may be different from the …
The Effect Of Interactivity And Instructional Exposure On Learning Effectiveness And Knowledge Retention: A Comparative Study Of Two U.S. Air Force Computer-Based Training (Cbt) Courses For Network User Licensing, Matthew J. Imperial
Theses and Dissertations
The United States Air Force (USAF) currently employs the use of computer-based training (CET) across a host of requirements. One such requirement is in the Information Assurance (IA) arena and involves the training/licensing of over one-million computer network end-users. USAF use of CETs has been shown to possess a potential for substantial fiscal savings. However, studies investigating the learning outcomes of learning effectiveness (initial learning) and knowledge retention (sustained learning) associated with USAF CETs are lacking.
The Effects Of Technology Turnover On Workplace Productivity Perceptions, Robert W. Povlich Jr.
The Effects Of Technology Turnover On Workplace Productivity Perceptions, Robert W. Povlich Jr.
Theses and Dissertations
The productivity paradox is a theory that suggests that investments in Information Technology (IT) do not necessarily lead to associated gains in the productivity of the organization (Malakoff 2000; Hitt and Brynjolfsson, 1996). This perception leads practitioners to question if acquiring new IT systems for the sake of having the latest technology will make their organization any more productive (Liebmann, 1996). Understanding the problem that is facing the practitioners, this research was undertaken to attempt to answer some of the underlying questions relating to the perceptions held about the relationship between IT expenditures and workplace productivity with respect to Air …
Text Manipulation Judgment Accuracy: An Exploratory Study, Randy S. Wardak
Text Manipulation Judgment Accuracy: An Exploratory Study, Randy S. Wardak
Theses and Dissertations
Deception aims to affect a decision-making process in a way that somehow benefits the deceiver. More knowledge is desired in the area of purely text-based scenarios. Thirty-seven graduate students at the Air Force Institute of Technology participated in an experiment in order to gain an initial understanding of how people determine whether text has been manipulated, and to identify specific areas that may be more closely investigated in future research. Excerpts were drawn from editions of a current-events newsletter that the participants receive on a weekly basis as part of their enrollment in the graduate program. Some of the excerpts …
Onward Movement Transportation Mode Selection Study, Seong Kyun Lee
Onward Movement Transportation Mode Selection Study, Seong Kyun Lee
Theses and Dissertations
As a result of global security environmental changes, the U.S. Army's posture has changed from forward deployment to power projection and resulted in the reduction of the Army force structure. These changes also reduce the possibility of the United States' involvement in a large-scale war, but require rapid and reliable deployment to stabilize a hostile area. Force projection is the demonstrated ability to alert, mobilize, deploy rapidly, and operate effectively anywhere in the world, and consists of three deployment segments: fort to port, port to port, and port to foxhole. Reception, Staging, Onward Movement, and Integration (RSO&I) is a detailed …
An Analysis Of Information Referenced Testing As An Air Force Assessment Tool, Eric D. Larson
An Analysis Of Information Referenced Testing As An Air Force Assessment Tool, Eric D. Larson
Theses and Dissertations
The Department of Defense (DOD) has placed a great deal of importance on training and education, throughout all areas of infrastructure development and force implementation. A more knowledgeable operating unit, in any situation, is consistently the deciding factor for success. The United States Air Force, too, has emphasized this ideal and sought to employ those persons most qualified for the required task. Yet, problems within the classroom and various training venues are always present and should be continually marked for improvement. Existing assessment techniques should provide an accurate account of the quality of information learned by DOD personnel. This is …
A Comparative Study Of The Warrior Support Tool And The Agile Munitions Support Tool, John C. Lofton Iii
A Comparative Study Of The Warrior Support Tool And The Agile Munitions Support Tool, John C. Lofton Iii
Theses and Dissertations
The purpose of this research is to ascertain if the United States Air Force (USAF) is duplicating effort with the development of the two IT applications, the Warrior Support Tool (WST) and the Agile Munitions Support Tool (AMST), or if one will effectively meet requirements. Specifically, this thesis sought to answer four research questions addressing customer needs for a munitions IT application, identifying the capabilities of the two research IT applications, determining how well each application met the needs of the customer, and determining how supportable each application was in terms of information needs versus existing munitions systems. A mixed …
The Air Mobility Planner's Calculator Improvements, Verification, And Validation, Frank W. Watson Jr.
The Air Mobility Planner's Calculator Improvements, Verification, And Validation, Frank W. Watson Jr.
Theses and Dissertations
In today's Air Force, we are constantly faced with meeting the mission under limited budget and equipment constraints. Any tools that make completing the mission easier are highly sought after, and rightfully so. The Air Mobility Planner's Calculator (AMPCALC) is one such tool. It gives the mobility planner flexibility in planning by allowing several different situations to be modeled. This paper recommends improvements to the model and provides the verification and validation of the model in an attempt to prove that the model is a useful tool for Air Mobility Command and the United States Air Force.
Evaluation Of The Mountain Wave Forecast Model's Stratospheric Turbulence Simulations, Mark S. Allen
Evaluation Of The Mountain Wave Forecast Model's Stratospheric Turbulence Simulations, Mark S. Allen
Theses and Dissertations
Stratospheric turbulence (Stratoturb) is a well-known hazard to aircraft in flight. Forecasting mountain waves, specifically the breaking of these waves, is necessary to accurately predict the presence of Stratoturb. The Air Force Weather Agency (AFWA) requested a product with the capability of forecasting Stratoturb at 30, 50, and 70 mb using model data currently available, To facilitate their request, the Mountain Wave Forecast Model (MWFM) was acquired from the Naval Research Laboratory. MWFM turbulence forecasts generated twice daily over East Asia, using the AVN and MM5 models for initialization, were compared to S' layer turbulence analyses from the Rawinsonde Observation …
Detection Of Special Nuclear Material With High Purity Germanium (Hpge) And Mercuric Iodide (Hgi2) Gamma Detectors, Michael B. Nelson
Detection Of Special Nuclear Material With High Purity Germanium (Hpge) And Mercuric Iodide (Hgi2) Gamma Detectors, Michael B. Nelson
Theses and Dissertations
The Defense Threat Reduction Agency (DTRA) contracted for two gamma radiation detectors: mercuric iodide (HgI2) and electromechanically cooled (EMC) high purity germanium (HPGe) to support arms control inspection efforts. This project investigated whether these detectors could measure the quality and quantity of special nuclear material (SNM), particularly Pu-239 for the treaty verification mission. The project investigated two areas of detector capabilities: 1) HgI2 and HPGe detector performance necessary to characterize the quality of plutonium and the presence of shielding materials and 2) HgI2 and EMC HPGe detector performance degradation by high noise levels and EMC HPGe …
Quantum Mechanical Calculations Of Monoxides Of Silicon Carbide Molecules, John W. Roberts Jr.
Quantum Mechanical Calculations Of Monoxides Of Silicon Carbide Molecules, John W. Roberts Jr.
Theses and Dissertations
Modern semiconductor devices are principally made using the element silicon. In recent years, silicon carbide (SiC), with its wide band-gap, high thermal conductivity, and radiation resistance, has shown prospects as a semiconductor material for use in high temperature and radiation environments such as jet engines and satellites. A limiting factor in the performance of many SiC semiconductor components is the presence of lattice defects formed at oxide dielectric junctions during processing. Recent theoretical work has used small quantum mechanical systems embedded in larger molecular mechanics structures to attempt to better understand SiC surfaces and bulk materials and their oxidation. This …
Total Dose Effects Of Ionizing And Non-Ionizing Radiation On Piezoresistive Pressure Transducer Chips, Samuel J. Willmon
Total Dose Effects Of Ionizing And Non-Ionizing Radiation On Piezoresistive Pressure Transducer Chips, Samuel J. Willmon
Theses and Dissertations
The effects of ionizing and non ionizing radiation on the resistivity of silicon based, piezoresistive bulk micro-machined chips from pressure transducers were examined. Standard current-voltage (I-V) measurements were taken in-situ and post-irradiation during isothermal annealing at room temperature. One group of chips was irradiated to a maximum total gamma dose of lMrad(Si) in the 11,000 Ci (60) Co gamma cell at Ohio State University. The second group of chips was irradiated at the Ohio State University Research Reactor facility to a maximum total neutron dose of 4 Mrad(Si) using beam port Hi. The resistivity was shown to decrease during gamma …
Using Sequence Analysis To Perform Application-Based Anomaly Detection Within An Artificial Immune System Framework, Larissa A. O'Brien
Using Sequence Analysis To Perform Application-Based Anomaly Detection Within An Artificial Immune System Framework, Larissa A. O'Brien
Theses and Dissertations
The Air Force and other Department of Defense (DoD) computer systems typically rely on traditional signature-based network IDSs to detect various types of attempted or successful attacks. Signature-based methods are limited to detecting known attacks or similar variants; anomaly-based systems, by contrast, alert on behaviors previously unseen. The development of an effective anomaly-detecting, application based IDS would increase the Air Force's ability to ward off attacks that are not detected by signature-based network IDSs, thus strengthening the layered defenses necessary to acquire and maintain safe, secure communication capability. This system follows the Artificial Immune System (AIS) framework, which relies on …
Data Mining Atmospheric/Oceanic Parameters In The Design Of A Long-Range Nephelometric Forecast Tool, Richard F. Benz
Data Mining Atmospheric/Oceanic Parameters In The Design Of A Long-Range Nephelometric Forecast Tool, Richard F. Benz
Theses and Dissertations
The Department of Defense calls for long-range forecasts to aid in the planning of operations. The goal of this research was to explore the feasibility of predicting, one month in advance, the total monthly cloud cover over the country of Afghanistan. In an attempt to reach this goal, the following objectives were achieved: (1) climatological synoptic study of Afghanistan; (2) survey of Real Time Nephanalysis, outgoing longwave radiation (OLR), and surface observational data; (3) examination of teleconnection indices and sea surface temperatures; (4) standard statistical analysis for prediction; and (5) classification tree analysis (CART), In addition, due to current world …
Linear Programming And Genetic Algorithm Based Optimization For The Weighting Scheme Of A Value Focused Thinking Hierarchy, David M. Thawley
Linear Programming And Genetic Algorithm Based Optimization For The Weighting Scheme Of A Value Focused Thinking Hierarchy, David M. Thawley
Theses and Dissertations
Deriving weights for a Value Focused Thinking (VFT) hierarchy demands considerable time and input from Decision Makers (DM) and Subject Matter Experts (SME). Often, the DMs and SMEs are the leaders of companies and organizations, and this required time is unrealistic with their schedules. In these situations, as well as scenarios where there no available DMs/SMEs, conventional means of weighting a VFT hierarchy are impossible, and any VFT analysis is halted. When historical data exists on evaluation measures and performance of alternatives, linear programming and genetic algorithm based optimization may be used to derive historically optimal weights for a hierarchy. …
A Framework For Prognostics Reasoning, Thomas C. Clutz
A Framework For Prognostics Reasoning, Thomas C. Clutz
Theses and Dissertations
The use of system data to make predictions about the future system state commonly known as prognostics is a rapidly developing field. Prognostics seeks to build on current diagnostic equipment capabilities for its predictive capability. Many military systems including the Joint Strike Fighter (JSF) are planning to include on-board prognostics systems to enhance system supportability and affordability. Current research efforts supporting these developments tend to focus on developing a prognostic tool for one specific system component. This dissertation research presents a comprehensive literature review of these developing research efforts. It also develops presents a mathematical model for the optimum allocation …
Active Processor Scheduling Using Evolution Algorithms, David J. Caswell
Active Processor Scheduling Using Evolution Algorithms, David J. Caswell
Theses and Dissertations
The allocation of processes to processors has long been of interest to engineers. The processor allocation problem considered here assigns multiple applications onto a computing system. With this algorithm researchers could more efficiently examine real-time sensor data like that used by United States Air Force digital signal processing efforts or real-time aerosol hazard detection as examined by the Department of Homeland Security. Different choices for the design of a load balancing algorithm are examined in both the problem and algorithm domains. Evolutionary algorithms are used to find near-optimal solutions. These algorithms incorporate multiobjective coevolutionary and parallel principles to create an …
Power Scaling Feasibility Of Chromium-Doped Ii-Vi Laser Sources And The Demonstration Of A Chromium-Doped Zinc Selenide Face-Cooled Disk Laser, Jason B. Mckay
Power Scaling Feasibility Of Chromium-Doped Ii-Vi Laser Sources And The Demonstration Of A Chromium-Doped Zinc Selenide Face-Cooled Disk Laser, Jason B. Mckay
Theses and Dissertations
Tunable lasers in the 2-4 µm wavelength range are needed for Air Force sensor applications. Chromium-doped II-VI materials are a promising class of laser material for tunable operation in this wavelength range, but until recently had not produced enough output power to meet application requirements. This dissertation investigates Cr2+:II-VI material properties and potential laser designs, then experimentally demonstrates and analyzes the performance of a Cr2+:ZnSe disk laser design that can produce sufficient output power. Cr2+:II-VI laser materials are found to be susceptible to overheating and thermal lensing, but are otherwise satisfactory laser materials. The …
Electromagnetic Scattering From A Gap In A Magneto-Dielectric Coating On An Infinite Ground Plane, George R. Simpson
Electromagnetic Scattering From A Gap In A Magneto-Dielectric Coating On An Infinite Ground Plane, George R. Simpson
Theses and Dissertations
The electromagnetic scattering from a gap in a magneto-dielectric coating on an infinite ground plane is analyzed. In this context, the gap forms a break only in the magneto-dielectric slab coating while the ground plane is continuous and unbroken. Volume equivalence is used to convert the gap region to one containing unknown volumetric equivalent electric and magnetic currents. The equivalent problem then is one of these currents radiating in the presence of an unbroken grounded magneto-dielectric slab. A Green's function for this geometry is developed consisting of two terms: a direct coupling term and correction term to account for the …
Finite Extinction Time For Non-Linear Absorption-Diffusion Equations, Jacob B. Goldberg
Finite Extinction Time For Non-Linear Absorption-Diffusion Equations, Jacob B. Goldberg
Theses and Dissertations
In this thesis, we develop a numerical method in order to approximate the solutions of one-dimensional, non-linear absorption-diffusion equations. We test our method for accuracy against a linear diffusion equation with a solution that can be written in closed form. We then test various types of diffusion and absorption terms to determine which ones produce extinction in finite time. We also develop a numerical method to computationally solve diffusion-free equations. We compare the numerical solutions of the one-dimensional, non-linear absorption-diffusion equation and the diffusion-free equation and we find that for the cases tested, the numerical absorption-diffusion solutions are always less …
High Energy Laser Pointing Through Extended Turbulence, Jason A. Tellez
High Energy Laser Pointing Through Extended Turbulence, Jason A. Tellez
Theses and Dissertations
The airborne laser (ABL) uses adaptive optics to compensate the atmospheric turbulence between the ABL and the target. The primary purpose of this compensation is to increase the energy density of the energy laser at the target. However, the specifics of the engagement scenario require the tracking point of reference and the adaptive optics point of reference to be located at different points on the target. This research considers the effects of tracking a target in one direction while compensating for atmospheric turbulence in a different directions. The target references used are a point source and a rectangle, while a …
Adaptive Harmonic Balance Method For Unsteady, Nonlinear, One-Dimensional Periodic Flows, Raymond C. Maple
Adaptive Harmonic Balance Method For Unsteady, Nonlinear, One-Dimensional Periodic Flows, Raymond C. Maple
Theses and Dissertations
A new adaptive split-domain harmonic balance computational fluid dynamics (CFD) method is developed to solve highly nonlinear time-periodic flows such as those found in turbomachinery. The basic harmonic balance CFD method transforms an unsteady time-periodic problem into a steady-state problem by assuming a solution in the form of a Fourier series in time. The new method employs a unique multi-domain split-operator solution technique to remove a large-series stability restriction present in previous harmonic balance CFD approaches. In addition, the new method adapts the frequency content to the flow, starting with a small number of Fourier frequencies and augmenting the frequency …
Mean Performance Optimization Of An Orbiting Distributed Aperture By Warped Aperture Image Plane Comparisons, Timothy W. Parker
Mean Performance Optimization Of An Orbiting Distributed Aperture By Warped Aperture Image Plane Comparisons, Timothy W. Parker
Theses and Dissertations
This work models the aggregate performance of satellite receiver formations functioning as orbiting interferometers as compared to filled apertures of similar geometries. These models facilitate selecting initial conditions for formations such that their control-free dynamics yield interferometry performance with minimal errors as compared to the filled apertures. The solution method draws on the dynamic models of an orbiting planar satellite formation to define the size and shape of a reference aperture and to define the degrees of freedom for the formation members. The paths of formation elements yield geometries for which the aggregate performance of the array of discrete receivers …
Comparing Clustering Algorithms For Use With Genomic And Proteomic Data, Rebecca A. Olson
Comparing Clustering Algorithms For Use With Genomic And Proteomic Data, Rebecca A. Olson
Theses and Dissertations
The Human Genome Project and related projects have resulted in the development of a number of new experimental and analytic tools for use in genomic and proteomic research. In the area of toxicogenomics, researchers are concerned with how genes react to exposure to certain chemicals. The United States Air Force is interested in the effect of exposure to mission-essential chemicals. Although military personnel may come into contact with chemicals such as hydrazine, risk assessment is usually very limited. On the genomic level, risk assessment is a multi-stop and multi-disciplinary process. The process begins with an experiment that exposes cells to …
Congruent Weak Conformance, Ronald W. Brower
Congruent Weak Conformance, Ronald W. Brower
Theses and Dissertations
This research addresses the problem of verifying implementations against specifications through an innovative logic approach. Congruent weak conformance, a formal relationship between agents and specifications, has been developed and proven to be a congruent partial order. This property arises from a set of relations called weak conformations. The largest, called weak conformance, is analogous to Milner's observational equivalence. Weak conformance is not an equivalence, however, but rather an ordering relation among processes. Weak conformance allows behaviors in the implementation that are unreachable in the specification. Furthermore, it exploits output concurrencies and allows interleaving of extraneous output actions in the implementation. …